Screaming or howling in Walker County, Georgia

My girlfriend and I traveled to this area at 11:30 that night to build a campfire and relax from the daily grind. She and I didn't have to work Wednesday, so the late hour didn't matter. At about 11:30 we found a suitable site, appr.7-8 miles in. There are only a dozen or so clearings for camping on the trail. Our site was on the trail, a clearing big enough to circle my truck around. It had two other trails at the back corners. One didn't go far before growth took over. The other looked like it might be passable, as far as I could tell. At 1 a.m. I was sitting on the tailgate and my girlfriend a few feet away tending the fire. Then we heard a loud high-pitched scream that reverberated through the dense forest. My girlfriend got scared and asked me what it was. I have been an outdoorsman my whole life, hunting, fishing, camping, and studying animals like a religion. I've never heard anything like that scream. I told my girlfriend to be quiet, maybe it would go off again. The moon was high and bright to be not full yet. The trail was lit good, so i looked down the trail and i looked the way we came. In the middle of the trail a large, bulky figure stood! The way the light fell on its features I believe it was facing me from about 30 yards distant. I thought at first it might be a tree or bush, but it had a discernable head, arms, torso, and legs. I went and got my girlfriend, not saying anything to upset her. If it turned out to be a tree, she would be mad for teasing her. I looked and the figure was gone! Back at the fire the 'animal’ behind us screamed same as before, except this time it sounded just inside the forest cover. Before we could react a similar, more distant call came from the forest in front of us. Was this the thing I had seen? I don't know. At that I threw everything in the truck at my girlfriend's panic. I shoveled sand onto the fire while she screamed hurry! I jumped into that truck and hit out a lot faster than we drove in!